Re: [PATCHv5 14/17] pps: capture MONOTONIC_RAW timestamps as well

Alexander Gordeev
2010-11-25T09:55:42Z

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В Wed, 24 Nov 2010 17:49:44 +0100 (CET)
Thomas Gleixner <tglx@linutronix.de> пишет:

> On Wed, 24 Nov 2010, Alexander Gordeev wrote:
> > /**
> > + * getnstime_raw_and_real - Returns both the time of day an raw
> > + * monotonic time in a timespec format
>
> IIRC then kerneldoc does not handle multiline comments for the
> function name

Ah, I see, fixed that.

> > + * @ts_mono_raw: pointer to the timespec to be set to raw
> > + * monotonic time
> > + * @ts_real: pointer to the timespec to be set to the time
> > + * of day
> > + */
> > +void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
> > +{
> > + unsigned long seq;
> > + s64 nsecs_raw, nsecs_real;
> > +
> > + WARN_ON_ONCE(timekeeping_suspended);
>
> Shouldn't this just return an error code instead of reading some
> stale or random value ?

Sorry, I don't know if it should, just copied it from getnstimofday().
BTW what is the bad value for timespec or you mean returning int
instead of void? I think this function should be handled the same way as
getnstimeofday() and no one currently expects that the latter can return
some bad value.

> > + do {
> > + u32 arch_offset;
> > +
> > + seq = read_seqbegin(&xtime_lock);
> > +
> > + *ts_raw = raw_time;
> > + *ts_real = xtime;
> > +
> > + nsecs_raw = timekeeping_get_ns_raw();
> > + nsecs_real = timekeeping_get_ns();
> > +
> > + /* If arch requires, add in gettimeoffset() */
> > + arch_offset = arch_gettimeoffset();
> > + nsecs_raw += arch_offset;
> > + nsecs_real += arch_offset;
> > +
> > + } while (read_seqretry(&xtime_lock, seq));
> > +
> > + timespec_add_ns(ts_raw, nsecs_raw);
> > + timespec_add_ns(ts_real, nsecs_real);
> > +}
> > +EXPORT_SYMBOL(getnstime_raw_and_real);
>
> Otherwise, I'm fine with that.
>
> Thanks,
>
> tglx

--
Alexander

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